[Elecraft] K3 Filter Option Questions (revisited yet again)

[Joe Subich, W4TV]

Phil, 

I chose to replace the 2.7 KHz filters with the 2.8 KHz 8-pole 
filters when I ordered my K3s and would not do so again.  If I 
were ordering a K3/KRX3 today, I would choose: 

13 KHz    FM and AM/SWL RX (waiting on Elecraft to lift the block 
          on using the FM filter for AM transmit). 
2.7 KHz   Match frequencies for main/sub RX 
open      reserve for 1.5 (INRAD) or 1.8 (Elecraft) KHz (narrow 
          SSB and band scanning) 
400 Hz  
200 Hz 

The subreceiver would have only the 2.7 and 400 Hz filters

The savings with matched 2.7 KHz and the 400 Hz filters vs. 
2.8 KHz and matched 500 Hz filters more than pays for one 
of the 8-pole filters (or would pay to fill the "open" 
slot). 

73, 

   ... Joe, W4TV 
   


> -----Original Message-----
> From: elecraft-bounces at mailman.qth.net 
> [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Phil Hystad
> Sent: Wednesday, December 23, 2009 2:41 PM
> To: Elecraft Reflector
> Subject: [Elecraft] K3 Filter Option Questions (revisited yet again)
> 
> 
> One of the things that I have not yet decided is the filters 
> to get for my K3 order.  I am firm on getting the 400 Hz 
> 8-pole filter (80 percent or so CW ops).  But, I like to scan 
> the band looking for signals with a wider filter, say around 
> 1 to 1.2 KHz.  Do I need to get the 1 K filter.  If I 
> remember right, I can set DSP filtering to about 1 KHz which 
> may be good enough or is there an advantage to the 1 KHz filter.
> 
> Also, is there a good reason to swap out the 5-pole 2.7 kHz 
> filter for the 2.8 KHz 8-pole?  I presume this gives the 
> filter sharper skirts so you can cut off those close stations 
> a bit better but I am curious as to how much better.
> 
> Since the dollar cost differences in decisions regarding 
> filters is not that great I would prefer answers that ignore 
> the cost issue.
> 
> So far, I am planning on getting the following filters with a 
> ? on the 1 KHz 8-pole and 2.8 KHz 8-pole:
> 
> 400 KHz 8-pole
> 1 KHz 8-pole  ??
> 2.8 KHz 8-pole swap for 2.7 KHz 5-pole ??
> 6.0 KHz 8-pole
> 
> 73,
> phil, K7PEH